As early as the
middle of the 11. century the Chinese knew the secret of manufacturing
solid powder rockets.But
powder is not stable enough for making large rockets, and therefore the
early pioneers like Goddard and von Braun concentrated on liquid fuelled
rockets.

In the middle of the
second world war
work was started on developing larger solid rockets for jet-assisted
takeoff (JATO). CALCIT/JPL in California developed a solid rocket based on asphalt mixed with an oxidizer.
Further
development work to the using of a polysulfide rubber
manufactured by a company called Thiokol instead af asphalt.

In 1949 JPL tryed to
scale up their rockets to develope a solid rocket with a diameter of 15 inches
–
the rocket was named sergeant.In
1950 the programme was cancelled because cracks in the internal structure
of the solid rocket led to explosions.

In the meantime Thiokol
went in to developing rockets of their own. They had showed, that they were able to
design large solid-propellant rockets like the falcon missile.

This was the reason,
that they in 1950 became subcontractors for General electric in the
developement of a large 31 inch solid rocket the Hermes A-2 later renamed as the
Hermes RV-A 10.

JPL was also participating in this projekt.

General
Electric was running the Hermes programme for the U.S. army. The Hermes
programme involved research in different kind of rockets including
American derivatives of the V-2 rocket, the german wasserfall rocket and
predecessors of the redstone missile.

After 22 static test firings, the first Hermes R-VA
10 was
launched in February 1953 followed by further 3 launches of the rocket.The Hermes RV-A 10 was newer developed in to a missile, but ithad proved, that it was possible to manufacture large solid rockets
of almost any size.The
Hermes RV-A 10 was therefore a significant step on the road leading to solid fuelled
missileslike the
minute man, and also to the large boosters, that we know from Titan 3C and
the space shuttle.

Note:The models noozle is based on pictures of the static testfirings
combined with the position of the vanes and drawings of the cancelled
tactical version XSSM-A-13.

Thanks to
Peter Alway for a second opinion on the nozzle
configuration.